1. Field of the Invention
The invention relates to a method for non-ferrous metal extraction, and more particularly to a method for extracting copper.
2. Description of the Related Art
Copper cinder is a byproduct from the process of high temperature pyrometallurgy. The main component of copper cinder is Fe existing in the form of ferrosilicate minerals and magnetic iron ore, besides, copper cinder further contains Cu, Pb, Zn, Al2O3, CaO, Sio2, S, and a small amount of gold and silver. The property of copper cinder is complicated, copper, for example, exists in the form of copper sulfide, metallic copper, and a small amount of copper oxide. The property of copper cinder is determined by the property of copper concentrate input into the smelter, smelting conditions, and the cooling process of the cinder. Furthermore, most of the precious metals coexist with copper, thus, copper as well as the precious metals can be extracted. As an important second metal resource, copper cinder contains many available resources. With the development of benefication technology, dilution-flotation technique used in copper cinder has achieved relatively ideal technical indexes. However, the conventional technology used to separate copper cinder containing more than 8.0 wt. % of copper cannot achieve such ideal technical indexes. Main factors are as follows: 1) in the conventional flotation process, copper cinders containing high level of copper are easy to deposit, thus the floatation of copper particles may be affected; 2) in the process of grinding, because of copper's malleability and large gravity, copper is easy to gather, which may affect the grinding efficiency, and the final particle size of copper may exceed the largest particle size for floatation. Therefore, according to the special property of copper cinder containing high level of copper, it is significant to seek a method with high efficiency and low consumption.